On Jun 29, 2017, at 2:11 PM, Andreas Dilger <adilger(a)dilger.ca>
wrote:
On Jun 29, 2017, at 5:58 PM, John Bent <John.Bent(a)seagategov.com> wrote:
>> On Jun 29, 2017, at 1:52 PM, Andreas Dilger <adilger(a)dilger.ca> wrote:
>>
>>>> On Jun 29, 2017, at 5:47 PM, John Bent <John.Bent(a)seagategov.com>
wrote:
>>>>
>>>> On Jun 29, 2017, at 1:35 PM, Andreas Dilger <adilger(a)dilger.ca>
wrote:
>>>>
>>>> That means the result needs to be in "files per second"
>>>
>>> Absolutely. It will be just a fifth iops number to combine with the other 4
IOPs numbers (mdtest create easy/hard and mdtest stat easy/hard) using geo mean.
>>>
>>> Figure out the number of files created by the four produce phases: n. Then
divide that by wall-clock for the find command: w. Then the 'find' IOPs is n/w.
>>>
>>> My concern is that it will be so slow that people will give up and not run
it.
>>
>> I don't see why that would be true? For Lustre at least, readdir() and
stat() are about 2x as fast as creating files.
>
> Even if you create across 10,000 nodes and then readdir from just 1?
Hmm, good point. I was thinking about parallel stat, but it isn't orders of
magnitude slower. George mentioned the find command took 3-4 minutes, which isn't
slower than the 5-minute create phase...
I don't think George has done a 5-min create phase yet. He's just getting
the scripts working still.
Thx
John
Cheers, Andreas